Israeli soldiers watch as an Iron Dome interceptor missile is launched on Nov. 18 near Ashdod. Iron Dome is designed to shoot down rockets and artillery shells. It has a range of 45 miles and has been operational since 2011. Ariel Schalit, AP

Smoke trails of rockets streak through the sky after Palestinian militants fired a volley of missiles at Israel on Nov. 19 from Gaza City. Hundreds of rockets have been fired into Israel. Hatem Moussa, AP

A Hamas militant carries a mock-up of a Qassam rocket during a march on Dec. 14, 2006, in the Nuseirat refugee camp, Gaza Strip. Qassam rockets are homemade missiles constructed from pipes and fitted with a small warhead. They are propelled with a solid fuel made from sugar and fertilizer. Adel Hana, AP

Israeli children look at the Iron Dome missile defense system on Nov. 17 in Gush Dan. There are five Iron Dome batteries and most are located near Gaza. The system has an 80% success rate. Roni Schutzer, AFP/Getty Images

An Israeli missile launched from the Iron Dome defense system on Nov. 15 hits a target. When the system detects a missile launch it quickly determines the target's flight path. If it is headed toward populated areas it fires an interceptor missile fitted with a special warhead that strikes the incoming rocket within seconds. Jack Guez, AFP/Getty Images